Treatment of precious metalliferous ores.



JOHN COLLINS CLANCY, OF NEW YORK, N. Y.

TREATMENT OF PRECIOUS METALLIFEROUS ORES.

Specification of Letters Patent.

Patented Nov. 15, 1910.

No Drawing. Original application filed July 12, 1909, Serial No.507,110. Divided and this application filed April 25, 1910.

Serial No. 557,399.

1 '0 all whom it may concern:

Be it known that I, JOHN COLLINS CLANoY, a subject of the King of GreatBritain, having declared my intention of becoming a citizen of theUnited States, at present residing at New York city, borough ofManhattan, in the county of New York and State of New York, haveinvented certain new and useful Improvements in the Treatment ofPrecious Metalliferous Ores of which the following is a specification.

I My invention relates to novel methods of treating ores bearing theprecious metals, which methods are particularly described and pointedout in the following specification and claims.

I have discovered that when a substantially non-acid solution ofathiocyanate containing such ore is oxidized the precious metals onlywill be dissolved to the substantial exclusion of the baser metals. Ihave also discovered that ozone either alone or in admixture with airmay be successfully employed as an agent for producing such oxidation. Ihave also discovered that said result may be accomplished by ozone witha solution of thiocyanate alone or in connection with cyanid. I havealso discovered that this process may be successfully applied to eitherrebellious or non-rebellious ores without preliminarily roasting eventhough such ores contain reducing agents or tellurium or both.

I give two following examples of my process without, however, limitingmyself to the details of either Example 1: 1000 pounds of pulverized oreare suspended in a solution of one pound potassium thiocyanate, poundcaustic lime or caustic soda and pound soluble iodin compound such aspotassium iodid, in 2000 pounds of water. 200 grams of ozone arethoroughly mixed with the solution. The ozone liberates the iodin fromits compound and the iodin acts on the thiocyanate to produce cyanid.The addition of the iodin compound also insures complete absorption ofany excess ozone which might escape without doing oxidation work.

Example 2: 1000 pounds of pulverized ore are suspended in a solution ofone pound potassium thiocyanate, pound potassium cyanid, 1} poundcaustic lime or caustic soda, 3; pound soluble iodid compound such aspotassium iodid in 2000 pounds water. 200 grams of ozone are thoroughlymixed with the solution. The action is substantially the same as in thelast example.

Although I have given a definite quantity of ozone in the aboveexamples, I do not wish to be understood that either this or the otherquantities given are invariable. The proper amount of ozone may bedetermined by titration or otherwise and with some ores as little as 15grams of ozone to 2000 pounds of solution have given good results.

In each of the above examples, the ozone may be either alone or mixedwith air.

In each of the above examples, the desired result is prevented if thesolution be substantially acid. Where cyanid is absent, as in the firstexample, the solution should be alkaline or neutral. Where cyanid ispresent, as in the second example, the solution may be alkaline, neutralor slightly acid. By slightly acid, I mean this: that while a solutionof potassium cyanid may be technically termed slightly acid becauseshowing acidity to certain tests, yet for practical purposes it issubstantially not acid. Such a solution I call a substantially non-acidsolution as well as those which are alkaline or neutral.

The strength of the solution is to some extent dependent upon thecharacter of the ore to be treated and the best strength shouldtherefore be ascertained by preliminary tests, but with ordinary oresthe strength that I have given in the foregoing examples answers well.The same solution can be used again and again by keeping up therequisite strength of its constituents.

It is not necessary to preliminarily roast the ore. If reducing agents,such as sulfides or iron are present, they do not act on the solution todecompose it. If tellurium is present, it is dissolved simultaneouslywith the precious metals.

Having thus described my invention and examples of different ways ofcarrying it into effect, it will be understood that variousmodifications and changes in the described processes may be made andequivalent substances may be employed without departing from the spiritof my invention and without exceeding the scope of my claims.

Vhile I have stated above that the process includes the use of asolubleiodin compound I desire it understood that the invention can becarried out by the use of one of the halogen compounds and that iodin ismerely referred to by Way of example as being the preferred halogencompound to be used in this; connection. 7 V L This application isadivision of my prior appli'cati-on Serial Number 507,110, filed July 12,1909.

What I claim and desire to secure by Letters Patent ofthe- United Statesis 1-. The method of treating ore containiurgv precious metals Whichconsists in subj e'ctin-gthe ore to the action of a thiooyanate and asoluble halogen compound and oxidizing the mixture. V I

21- The method of treatingore containing precious metals which consistsin subjecting the; ore' to the action of a thiooyanate' and a solubleiodin compound and oxidizing the mixture.

3. The method of treating ore containing precious metals which consistsin subjecting the ore; to the action of a thiocyanate and a solublehalogen compound, and oxidizing saidmixture by means of ozone.

4E. The method of treating ore containing precious: metals-Whicliconsists in subj'eefing the said ore to the action of athiocyanate and a soluble iodin compound, and oxidizing said mixture bymeans of ozone.

In testimony whereof I havehereunto signed my name the presence of twosubscribing. Witnesses.-

J OHN COLLINS CLANCY.

Witnesses 5- M. E.- MoNINoH', (1- G.-

